Coal stoker



March 1 9', 1946.

E. STRANG COAL STOKER 2 Sheets-Sheet 1 original' Filed Feb. 19. 1943 March 19, 1946. E A. STRANG COAL STOKER original E iled Feb, 19, 194s 2 Sheets-sheet 2 fff Patented Mar. 19, 1946 UNITED- STATES PATENT OFFICE assess-9 CoA-L s'ronine` Earl A. Strang, Waukegan, Ill. original applicaticn Februaryie, 1943, serial No.,

Divided and this application March.

19, 1945, seria1Na5sae22 'a claims. (c1. 1104-46) nism. Another object is-to provide a stoker in,

which the driving mechanism performs the. triple function of feeding the coal, co-operating with a ratchet mechanism to shake the hopper and rio-operating with an agitator to keep the exit tube clear of obstruction.

Another-object is to create a stoker in which the exit tube is positioned between the re pit and the hopper so as to provide an exit to prevent the gases from reaching the hopper and causing combustion therein anclfrom reaching and in-A teriering withthe stokei` mechanism. My invention contemplates such other objects, advantages and capabilities as will later more fullyl appear and which are inherently possessed by my in vention.

While I have shown in the accompanying drawings a preferred form of my invention, yet I wish it understood that the same is susceptible of modication and change without departing from the spirit of my invention.

Referring to the drawings, Fig. 1 is a side elevational View of my stoker; Fig. 2 is a top plan view of the same with the hopper removed; Fig. 3 is a detailed sectional view of the hopper and tube construction; and Fig. l is a top plan View in section to show operating parts in related positions.

The embodiment selected to illustrate my invention comprises a burning pit or retort I0, receiving one end of a hollow pipe or tube II.

A bearing or hopper support casting I2 is attached to said tube II and has an opening I3 communicating with an opening I4 in the tube. The casting I2 has a top flange I5 on which is mounted a filler ring I6 about which is positioned a pawl ring I1, having an ear I8. A rotatable ratchet member I9 has a circumferential groove 20 to receive ller ring I8. The ratchet member I9 has a plurality of ratchet teeth 2l. A pawl housing 22 having a pawl 23 is pivotally attached to ear I8 of pawl ring I1. The casting I2 extends upwardly on an angle as shown at 2t sc that hopper 25 attached to ratchet member I9 extends diagonally upwardly. The bolts 26 attaching hopper 25 to ratchet member I9- may be removed and .hoppery 2 5 tilted Von hinge 21.

The tube II extends from the. retort Ist-to the gear box 28'. Movablek within tube II isa plunger 29-having a shoulder head 30 at'one end, and a pairv of oppositely disposed lugs. 3'I adjacent. A

other end. Plunger- 29 is hollow and withinuits interior, screw 3,2 is iixed with one end of said screw attached within shoulder head 30;, A driving: tube 33'has a. threaded portion 3.4 fitting around the free end 35 of the plunger screw 32. Driving tube 33jl is, of course, hollow to the extent of screw 32 sov as to accommodate the. same. Ex-

tending beyond the. driving tube 33 isL ay driving .gear 84. A jack shaft'85 with three gearsy transmits motionv from motor 38, through belt driven worm gearing 31 to reversing clutch shaft. 38 and intermediate pinion gear 39 to drivingV gear 34 and thence to plunger screw .32. The driving mechanism may bev controlled by suitable switch Vor thermostat means (not shown) so as to provide desired back and forth movement of the plunger 29.

A ratchet pull rod 48 is slidably mounted in `bearings 4I attached to tube II, and has .eye 42 at one end for the attachment of cable 43', and a stop pin`44 adjacent its other end. The cable 43 extends through pulley 45 bracketed to tube II, and then to the pawl housing 22. A draw spring 46 extends between the pawl housing 22 and an anchor bolt 41 which is attached to casting I2. An arm 48 is attached to pull rod 40.

A gas vent rod 49 is slidably mounted through an opening in the lower portion of arm 48, and has a stop member 59 therebeyond. Said rod 49 is coupled to bell crank 5I, which extends into escape gas flue 52 and has therein a pair of agitators 53.

The escape gas flue 52 is located between the retort I0 and the hopper I2 to prevent exhaust gases from reaching the hopper and other parts of the mechanism and has a stub for the attachment of suitable smoke exit means.

Tube I I has a pair of oppositely disposed slot-s 54 adapted to slidably receive spaced lugs 3|.

Near each of the opposite ends of the feed stroke are positioned resilient shift arms 55, which are adjustably attached to shift rod 56 which is attached at one end to a bearing 51 in the gear` housing 28, and at the other end to a bearing 58 attached to the casting I2. Within gear housing 28 a shifting'fork 59 is attached to shift rod 56 and operates a clutch 38 for reversing direction of the plungel` 29 adjacent the outer end of shift rod 56 are a plurality of detents 60 to receive spring plunger 6l positioned in bearing 51 to hold shift rod 5B from moving out o desired position.

A wind blower 62 .is provided with a duct 63 leading into shroud 64 surrounding fire pit I0.

In use, coal is placed in the open upper end I5 of hopper 25 and falls by gravity as it is used through openings 4I3 and I4 into tube Il. AdjustableV shift arms 55 having been set as desired, and the motor 36 having been turned on, at the desired time, plunger 29 moves forwardly, contacts the coal which has dropped into tub l l and pushes it ahead into the re pit 10. Near the end of the feed stroke one of lugs 3| strikes against one of the resilient shift'arms 55 to move shift rod 56 and shifting fork 59 so as to engage clutch 38 and provide reverse movemen f of the plunger 29.

On the return or idle stroke a lug 3| strikes arm 48 to move pull rod 40 and cable 43 so that pawl 23 engages a tooth 2| of ratchet plate 20 and moves it for a distance of aboutone tooth. This turns the hopper, and prevents V,clogging of the same, thereby providing an even 'and full supply of coal; it being noted that at the time thatthe hopper is shaken, the plunger 29 is ready to'free openings i3 and I4 for the ready reception of coal by the tube vl l.

- .,A't the same time that lug 3l strikes arm 48 and actuates the vhopper shaking mechanism, the arm 48 ist moved on gas vent rod 49 until it hits stop member 5U. This provides a slight delay in moving rod 49, bell crank 5l and agtators 1 53 within escapegas flue 52. The agitators prevent clogging of the escape gas flue 452 with sooty particles and clears the passage of gaseous fumes.

Near the endof the stroke lug 3l contacts the opposite resilient vshift arm 55 for again reversing the direction of travel of the plunger 29.

Having thus described my invention, I claim: j 1. In a Stoker, having `a fire pit, a tube having one end extending into said nre pit, a hopper rotatably mounted on said tube and communieating therewith, a' plunger within said tube, 'adjustable and automatic means for driving said plunger back and forth within said tube, an

escape gas flue attached to and communicating with said tube between said nre pit and said hopper, a pull rod slidably attached to said tube, a cable attached to said pull rod, ratchet means in communication with said cable, said ratchet means mounted on said hopper, an arm attached to said pull rod, a gas vent rod attached to said arm, a bell crank pivotally attached to said vent rod, an agitator attached to said bell crank and extending within said escape gas flue, said tube having a slot, said plunger having a lug extending through said slot, said lug upon rearward movement of said plunger contacting said arm said arm moving said pull rod,

- cable and ratchet means to slightly rotate said hopper, said arm also moving said gas vent rod andbell crank to actuate said agitator within said escape gas flue.

2; In a Stoker, having a horizontal tube, a hopper mounted on said tube and communicating therewith, a hollow covered plunger of slightly less diameter than said tube, said plunger slidable within said horizontal tube, a screw completely positioned within said plunger, a shoulder head attached to the front end of said screw said shoulder head forming the front end of said covered plunger, a driving member within said tube and having a screw threaded nut for engaging said screw, means for actuating said driving member so that its threaded vnut co operating with said screw moves said plunger forwardly and said shoulderhead pushes forwardly coal dropped into' said tube from said hopper and means for oppositely actuating said driving member so that its threaded portion cooperating with said screw moves said plunger rearwardly beyond where said hopper communicates with said tube so as to permit coal to drop from said hopper into said tube, said covered plunger adapted to close communication between said hopper and said tube when said covered plunger is forward of said hopper, said covered plunger also adapted to prevent coal from entering its hollow interior at all times and clogging said screw.

EARL A. STRANG. 

